That "word" has already gotten me business from experienced pilots. The experienced pilots are the ones that are MORE impressed than the beginners, since the beginners don't even know what "CFI" stands for.
Like I said, if you are gonna pay for a renewal ANYWAY, then why not pay NAFI and get the extra "word". Like I recently got the "word" ATP added to my name. "Words" mean a lot to folks, especially when it denotes professionalism, experience, "been there done that", etc.
The economics makes sense. Pay NAFI, get your Master, or pay Eagle-something-or-other and get your CFI "renewal". Also, I have found in the past that the ones that "don't have" are usually the ones that complain and say that "it isn't worth it". It is a lot of work to get AND to renew.
Also, my advice comes from "me", a SUCCESSFUL CFI that turns down students because I am too busy, charge and get $45/hr with no questions.
Bottom line, I will take the "word" since it is greatly helping out my already sucessful profession.